Voltage-regulator.



E. LEHR.

VOLTAGE REG APPLICATION FXLED JULY 19, M3.

ULATOR.

Patented June 29, 1915.

3 SHEETSSHEET l.

E. LEHR.

VOLTAGE REGULATOR.

APPLICATION FILED JULY 19. 1913.

1,1%, 64, PatentedJune 29, 1915.

3 SHEETS-SHEET 2.

E. LEHR.

VOLTAGE REGULATOR. APPLICATION FILED JULY 19, 1913. y Patented June 29,1910.

3 SHEETSSHEET 3 wnwzssas:

EN NEQR ii mw f "7' A E r I MM W ATTORNEY UENITED STATES PATENT ()FFIOE.

EDWIN LEZHR, 0F WILKINSBUBG, PENNSYLVANHL, ASSIGNOR TO WESTINGHOUSEELEC- TRIC AN'D MANfiFAGTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

VOLTAGE-REGULATOR.

Specification of Letters Patent.

Patented June 29, 1915.

Application filed July 19, 1918. Serial No. 780,012.

To all whom it may concern Be it known that I, EDWIN LEHR, a citizen ofthe United States, and a resident of Vvilkinsburg, in the county ofAllegheny and Stateof Pennsylvania, have'invented a new andusefulImprovement in Voltage Regulators, of which the following is aspecification.

My invention relates to. voltage regulators and it has special referenceto regulators of the step type such as are employed to control thevoltage of transmission lines.

My invention has for one of its objects to provide a device of the aboveindicated character in the operation of which destructive sparking atthe contact segments is avoided.

My invention also has for an object to provide aregulator in which isembodied an automatic mechanism .for the operation of the contact arms.7

Voltage regulators, as commonly con structed heretofore, comprisemovable arms which operate to successively engage contact segments ofdifferent potential. When the contact arm leaves one segment, an arcfollows, and an are also precedes the engagement of. the arm with thesucceeding segment. The contact segments are,therefore, rendered unfitfor efficient use in a comparatively shor time and expensive repairs arerequired atfrequent intervals.

I propose to provide a second or auxiliary arm which operates to make apreliminary contact with one segment before the main arm leaves thepreceding contact segment. Automatic mechanism operates to change thecircuit connections from one arm to the other in such manner that thearm which is making or breaking contact is not connected in circuit. Thecircuits are made and broken during thesechanges by suitable oilimmersed switches, and destructive sparking between the arms andsegments is thereby avoided.

The detailsof my invention will be described in connection with theaccompanying drawings in which F igurel is a front view, partially inelevation and partially in section, of a regulator constructed inaccordance with my invention, arts being broken away. Fig. 2 is an-enview, partially in elevation and partially in section, of the regulatorshown in Fig. 1. Fig. 3 is a detail view of a star wheel. Fig. 4a is adetail view of a .cam mechanism. Figs. 5 and 6 are views in section andin elevation, respectively, of gear mechanism. Fig. 7 is an end view ofa locking mechanism. Fig. 8 is a diagrammatic view ofcirc'uits andapparatus embodying my invention.

Referring particularly to Figs. 1 and 2, the regulator comprises asuitable frame that is indicated broadly at 1. The regulator comprises apair of '-units which are structurally alike, and the description willtherefore be limited to one of them. A dial 2' is mounted uponandinsplated from the frame 1. The front face of the dial is providedwith a number of contact segments 3 which are arranged in a circle aboutthe center of the dial and are adapted to coact with a rotatable contactarm 4. The arm 4 is mounted upon a shaft 5 which is connected tooperating mechanism later described. The rear face of the dial is alsoprovided with a corresponding-number of oppositely disposed contactsegments 6, each of which is electrically connected to a cor-- Irespondlngsegment 3 upon the front face of the dial. The shaft 5 isprovided with an auxiliary contact arm 7 which is insulated therefromand which coac'ts with the contact segments 6. The arm 7 is providedwith a contact member 8 which is in constant engagement with a slip ring9. The arngs 4 and 7 are so arranged that, when either arm is incomplete engagement with its respective segment, the other arm isentirely disengaged. Both the arms 4 and 7 may, however, be partiallyengaged at the same time with adjacent pairs of segments or with thesame pair of segments. The regulator comprises two pairs of oilimmersedswitches 10 and 11. The switches 10 control the circuit connections ofthe main contact arms 4 and the switches 11 control the circuitconnections of the auxiliary arms 7. The switches are operated in theirproper sequence by the same means, in part, that are employed to actuatethe contact arms.

The meclhanism for controlling the contact arms 4 and 7 and the switches10 and 11 comprises a shaft 12, one end of which mittent bevel gearwheels 20.

is provided with a crank 13. The shaft 12 is provided with a star wheel14 having a notch 15 that is normally engaged by a roller 16. The roller16 is carried by an arm 17 that is drawn toward the wheel 14 by a spring18.

The shaft 12 is also provided with mutilated bevel pinions 19 whichactuate inter- The gear wheels 20 are mounted upon shafts 21 which areconnected to, and insulated from, the Each of the pinions 19 1s pro-.vided with a locking ring 22 having notches shaft 5.

,a lever 30'.

The electrical circuits are illustrated in Fig. 8. An incomingthree-phase transmission line consists of conductors 32, 33 and 34. Theconductor 32 is connected to each of conductors 33 and 34 throughtransformers 35 and 36, respectively. Thetransformers compris'e primarywindings 37 and 38 and secondary windings 39 and 40. The secondarywindings are divided into sections 41, the common points of which areconnected to the contact segments 3. The voltage of the outgoing line isregulated by the number of sections connected in circuit by the contactarms.

Two resistors 42 are controlled by the switches 11 and are each adaptedto be placed in circuit with one of the auxiliary arms? when the lattercarrycurrent. The resistors 42. operate as a preventive resistance orsafety device during the temporary use of the arms 7. A currenttransformer 43 may supply current to any suitable instrument.

It may be assumed that the arms 4 and 7 occupy the positions shown inFigs. 1 and 8. Thecrank handle 13 is in its vertical or runningposition, the intermittent gear wheels are in mesh, the main switch 10is closed and the auxiliary switch 11 is open. Current flows through themain arms 4, while the circuits of the auxiliary arms 7 are open. Theactuation of the crank handle 13 through a complete revolution producesa series of operations in the sequence stated below. The main arms4aremoved in a clockwise direction partially are out of mesh. The auxiliaryswitch 11 then closes the circuits of the auxiliary arms 7 through therespective resistors 42, and the main switches 10 subsequently open tobreak the circuit of the main arms 4.

The continued actuation of the shaft 12 again brings the gear wheels 19and 20'into mesh, and the arms 4 are moved entirely off the segments andpartially into engagement with the succeeding segments. The arms 7, atthe same time, move to a central position relative to the segments andthen to partial engagement. The arms 4 and 7 now engage the same pair ofconnected segments. The cams next effect the closing of the mainswitches 10 and the opening of the auxiliary switches 11, in order. Themain arms 4 are then in circuit and the auxiliaryarms 7 aredisconnected. The gear wheels are again brought into mesh by continuedrotation of the shaft 12, and the arms 4 are moved to a central positionon the segments, the auxiliary arms 7 taking a position midway betweenthe segments. The notch 15 of the star wheel 14 is again engaged by theroller 16 to retain the shaft 12 and the connected mechanism in theirrespective positions. The

various parts are now in their normal running positions.

It will be readily understood from the above description of theconstruction and posite direction to that above described, the

sequence of operations is reversed and the voltage. is correspondinglyalfected.

While I have described my invention in its preferred form, it isunderstood that such changes and modifications may be made as fallwithin the limits of the ap' pended claims. I

I claim as my invention 1. The combination of a plurality of stationarycontact members, and a plurality of coacting movable contact memberswhich are fixed relatively to one another, of means for automaticallycontrolling the electrical connections of said movable members as theyare moved relatively to said stationary members.

2. The combination with a plurality of stationary contact segments, amain contactarm, and an auxiliary contact arm, of electrical circuitsfor said arnhs, and means for automatically opening and closing thecircuits of said arms when said armsare simultaneously moved relativelyto said segments.

3. The combination with a plurality of stationary contact members,movable main and auxiliary contact members which are fixed relatively toone another, and electrical circuits for said members, of means forautomatically controlling the circuits of said movable members inaccordance With their positions relative to said stationary members. 4.The combination with a plurality of stationary contact members, movablemain and auxiliary contact members which are fixed relatively to oneanother, and electrical circuits 'forsaid members, of means forautomatically controlling'the circuits of said movable members inaccordance with their positions relative to said stationary members. v

- '5. The combination withaplurality of stationary contact members,and'movable main and auxiliary contact members which are fixedrelatively to oneganother, of means including electrical connections,for opening andclosing the circuits of said? arms only whenin engagementwith said contact mem- 6. The combination with a plurality of stationarycontact members, and-a pair of coacting movable-centact members arrangedto successively engage said stationary members, said movable membersbeing so related as to simultaneously engage succes sive stationarymembers, of means for simultaneously controlling the positions and theelectrical connections of, said movable members; T

7. The combination with a plurality of stationary spaced contactmembers, and a plurality of coacting movable contact members which arefixed relatively to one another, of means for automatically opening thecircuits] of said movable members before being disengaged from saidstationary contact members and for closingsaid circuits after saidcontact members are in engagement. 7

8. The combination with a plurality of stationary contact segments and apair of mov able contact arms for successively engaging said segments,of electrical circuits for said segments and said arms, and means .for'controlling the circuits of said arms in accordance with the positionsof said arms relatively to said segments.

9. In a regulator', the combination with a plurality of stationarycontact members, and a plurality of movable contact members which arefixed relatively to one another for successively engaging saidstationary members, of means for alternately connecting said movablemembers in circuit as they fire moved relatively to said stationary mem-10. In a regulator, the combination with a plurality of stationaryspaced contact members, a plurality of coacting movable contact memberswhich are fixed relatively to one another, and electrical connectionsfor said movable contact members, of switches for controlling saidconnections, and means for alternately actuating said contact membersand operating said switches.

11. In a regulator, the combination with a plurality of stationaryspaced contact members, a plurality ofcoacting movable contact memberswhich are fixed relatively to one another, and electrical connectionsfor said movable contact members, of switches for controlling saidconnections, and means comprising an intermittent gear mechanism foralternately operating said switches and actuating said movable contactmembers. i

In testimony whereof I have hereuntosubscribed my name this 16th day ofJuly EDWIN LEHR. Witnesses:

E. A. HAUFF, B. B. Hnms.

